The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 17, 1994
Filed:
May. 12, 1992
Applicant:
Inventor:
Youngky Kim, Potomac, MD (US);
Assignee:
Hughes Aircraft Company, Los Angeles, CA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04L / ;
U.S. Cl.
CPC ...
375 94 ; 375101 ;
Abstract
A lower order Viterbi system for estimating symbols being transmitted over a digital cellular channel. The received signal is oversampled at a rate at least twice the frequency of the symbol duration. The energy contained in the main and interference symbol signal is thus sampled and permits a superior BER to be obtained. The branch metric for the lower order Viterbi algorithm is calculated using both signal samples. Channel status information is individually estimated for both samples, further improving system BER. The channel status is obtained for both frequency offset errors, amplitude fading and phase occurring within the channel.